Ephesus
Writing

Notes from the build

Everything here comes out of this project’s own records rather than from opinion. Where a post describes a defect, that defect was real, it was found on a stated date, and the fix is in the repository.

design 5 min read

Why the crew works in its own checkout

Running several agents in the architect’s working tree is fine until it isn’t. The fix was a worktree each — and the interesting part was what that broke.

method 5 min read

Forty green tests, nine killed mutants, and three ways past the gate

A new coverage gate passed its own tests, survived mutation testing, and was defeated three times in ten minutes by someone actively trying to walk through it.

method 7 min read

The recurring defect of this codebase is a check that cannot fail

Five instances found in a single day, in five different subsystems, by five different routes. The pattern was not carelessness — every one of them was written by someone trying to be careful.

decision 4 min read

The MVP ships one engine, and says so

Ephesus is designed around an engine-agnostic adapter seam. It ships with exactly one engine wired — and the decision record exists mostly to stop that being misread in both directions.

defect 5 min read

A green suite over 1,406 lines nothing could reach

A milestone shipped a subsystem that was fully implemented, fully tested, and never once called by the application. Every test passed. The feature did not exist.

design 6 min read

A research department that must cite a commit or die

The Stoa reads other people’s repositories and reports what it finds. The rule that makes it trustworthy also caught it citing a commit that existed in no repository at all.

design 6 min read

A project whose primary mission is its own improvement

The Gymnasium lets the company propose changes to itself. Everything interesting about it is in the constraints — a falsifiable metric before any human reads it, and a ledger that keeps the rejections.